Method and apparatus for installing new packing on a propeller shaft



- March 11, 1969 A. HENDRICKSON 3,432,172 METHOD AND APPARATUS FORINSTALLING NEW PACKING ON PROPELLER SHAFT Filed NOV. 25, 1966 Sheet of 5mnun"wnnnnnnnn nnnnnnnnnnnn 'III'III "A i 1 INVENTOR. ALLEN L.HENDRICKSQN QIZQIQSWJFQ ATTORNEYS March 11, 1969 A. L. HENDRICKSON3,432,172 METHOD AND APPARATUS FOR INSTALLING NEW PACKING O'N PROPELLERSHAFT Filed NOV. 25. 1966 Sheet '3 of5 EHHH'MIHHHHHHHHHHHH F |G ..12 3sf n 22 34 m" ll FlG 13 38 56 ALLEN L HLL D QFL QSON Elma. 2444,

ATTORNEYS March 11, 1969 A. L. HsNorglgK soN 3,432,172

METHOD AND PP TUS STALLING NEW PACK PROPELLER SHAFT Filed NOV. 25, 1966Sheet 2 0f 5 FIG...7

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ALLEN L. HENDRICKS'ON BY ATTORNEYISH United States Patent Ofi 3,432,172Patented Mar. 11, 1969 ice 3,432,172 METHOD AND APPARATUS FOR INSTALLINGNEW PACKING ON A PROPELLER SHAFT Allen L. Hendrickson, Redwood City,Calif., assignor of one-half to Olga T. Hendrickson, Redwood City,Calif.

Filed Nov. 25, 1966, Ser. No. 597,069

US. Cl. 277-1 7 Claims Int. Cl. F16 15/26 ABSTRACT OF THE DISCLOSURE Amethod and apparatus for adding new packing to the stern gland of aships propeller without drydocking the vessel. An apparatus is providedfor temporarily securing the old packaging within the stern gland whilethe new packing is brought into engagement with the means holding theold packing in place. The temporary means is then removed, and the newpacking is forced into the stern gland in contact with the old packing.No changes of any kind in the structure of the stern gland are requiredfor using the method and apparatus of the invention.

This invention relates to a method for installing packing around shaftsand also to a unique apparatus for carrying out the method.

In large ocean-going ships a packing must be provided around thepropeller shaft to prevent the influx of water into the ship along theshaft. Since the propeller in most large vessels is located at asubstantial depth this packing is normally subjected to severe waterpressure. Consequently, the packing must fit tightly around the shaft inorder to seal it and counteract the environmental pressure. Usually, thepacking is in the form of a series of circular members which areadjacent each other and extend longitudinally along the shaft within itsbearing shell. Due to the tight seal that must be maintained and theconstant rotation of the shaft, the packing is ordinarily subjected toconsiderable wear, and it is necessary to add new packing rings ormembers periodically to replace the worn out members.

Prior to the present invention the additional propeller shaft packingthat is periodically required could be changed or installed only whenthe propeller was out of the water because there was no way tocounteract the severe water pressure during the changing operation. Thismeant that either the ship had to be placed in dry-dock or its bowballast tanks had to be filled temporarily so that the ship would tipforward and its stern extend upwardly with the propeller out of thewater. Both of the foregoing procedures were extremely costly in moneyand in time.

A general object of the present invention is to overcome the aforesaidproblem and to provide a method for changing or installing the packingaround a propeller shaft of a ship while the propeller remains at itsnormal level below the water level and thus without putting the ship indry-dock or raising its stern in any manner.

Another object of the present invention is to provide a method forinstalling new packing to a propeller shaft of a ship whereby the oldpacking can be restrained against the force produced by the waterpressure around the propeller while the packing gland is removed and thenew packing is installed around the propeller shaft.

Still another object of my invention is to provide a method for addingnew packing around a shaft that counteracts the forces around the shafttending to displace the packing and yet can be performed by one person,in a relatively short period of time, without the need for complicatedand expensive equipment.

As will be apparent from the detailed description that follows, mymethod steps for supplying additional packing around the propeller shaftof a ship while the propeller is at its normal depth is most effectivelyaccomplished by a unique combination of relatively simple but uniquetools or apparatus which thus provide another feature of the presentinvention. The latter solve the problem of restraining the remaining oldpacking and holding it in place against the axially directed force ofthe outside water pressure when the packing gland is removed in order toinstall more packing ring members.

It is thus a further object of my invention to provide an apparatus foruse in installing new packing to a propeller shaft of a ship while itspropeller is in the water and in particular that provides a barrier torestrain the old packing, that enables the barrier to be forced radiallybetween the old packing and the packing gland, and that compresses thenew packing around the shaft so that it can be moved into place adjacentthe old packing.

Yet another object of my invention is to provide an apparatus forperforming a method of installing new packing to a propeller shaft thatis relatively inexpensive to manufacture as well as being easy tooperate in performing the method.

Other objects and advantages of the invention will appear and the aboveones will be explained more clearly and understood better from thefollowing description of a preferred embodiment of the inventionpresented in accordance with the statutes.

In the drawings:

FIG. 1 is a fragmentary schematic view in side elevation showing atypical propeller and shaft installation on an ocean type vessel;

FIG. 2 is an enlarged fragmentary view in elevation and in sectionshowing the propeller shaft of the ship in FIG. 1 with its packing inthe normal sealing postion;

FIGS. 3-6 are views similar to FIG. 2 showing progressively the steps ofa method for adding new packing around the shaft according to thepresent invention;

FIG. 7 is an end view showing one of the barrier members according to myinvention;

FIG. 8 is an enlarged fragmentary view showing a spacer member used inthe method of the present invention;

FIG. 9 is a view in section taken along line 9-9 of FIG. 8;

FIG. 10 is a view in section of a propeller shaft showing barriermembers and spacer members in position during the installation of newpacking according to the present invention, a portion being broken awayto show the packing;

FIG. 11 is a view in section of the propeller shaft of FIG. 10 showing aclamping band for use in installing additional packing;

FIG. 12 is an enlarged fragmentary view in elevation and in section ofthe clamping band around new packing being installed according to theinvention;

FIG. 13 is a view similar to FIG. 12 after the packing gland and the newpacking have been moved into their normal position.

The method of the present invention for installing additional packing orreplacing the packing around a rotatable shaft in a gland may be appliedto various shaft installations. However, it is particularly useful wherefluid pressure is present at the end of the shaft gland and constantlytends to push the packing out of its sealing position in the gland.Thus, it overcomes the problem of counteracting the environmental fluidpressure to hold the old packing in place and prevent leakage when thepacking gland is retracted from its normal position. In broad terms, mymethod comprises the steps of moving the packing gland axially until itsend is aligned radially with the flange of the shaft gland; providing aradially extending barrier extending circumferentially around the shaftand located between the end of the packing gland and the old packing;retracting the packing gland further to provide a space between its endand the end of the shaft gland to receive new packing material;confining the new packing material around the shaft and moving itagainst the temporary barrier; then removing the barrier and forcing thenew packing and the packing gland into the normal sealing positionwithin the shaft gland.

As a typical application, I will now describe my method in greaterdetail as it may be used to solve the problem of replacing the packingon the propeller shaft of a large ship.

Referring to the drawing, FIG. 1 shows schematically a stem end of avessel having a propeller 22 connected to a shaft 24 that extendsthrough a stern gland 26 fixed to the ships hull. As shown in FIG. 2,the shaft is sealed by a packing 28 between it and the stern gland whichis retained by an annular packing gland 30 that is accessible frominside the hull. In the case of large ships, the depth of the propellershaft below the waterline may normally be as much as -50 feet. At suchdepths the water pressure is substantial and constantly pushes inwardlyalong the shaft against the packing which is retained by the packinggland. In the typical installation shown in FIG. 2, the packing glandhas a radial flange 32 at one end attached to a sleeve portion 34 thatfits around the shaft and extends within the end of the stern gland withits end face 36 adjacent the packing. The stern gland also has a radialend flange 3 8 in which are mounted a series of circumferentially spacedapart studs 40. Threaded t0 the studs are a first set of nuts 42 thatnormally are taken up to be flush with the radial flange 38. The studsextend through aligned openings in the end flange 32 of the packinggland 30, and threaded to the ends of the studs is a second series ofnuts 44. Any take-up of the latter nuts causes an axial movement of thepacking gland on the shaft, and as the packing of a shaft graduallywears these nuts are periodically tightened.

Having described a typical shaft installation for a ship, I will nowdescribe the detailed steps of my method for installing additionalpacking.

The first step of my method is to provide a temporary barrier around theshaft at the end of the sleeve to prevent axial movement of the packingwhen the packing gland is retracted. To accomplish this, I provide aseries of rigid sectors 46 which may be made from a suitable metal.lEach sector has arcuate shape in plan form with a curvature along oneedge 48 that preferably approximates that of the shaft surface. (SeeFIG. 7.) This curved inner edge of each sector is preferably tapered incross section to a sharp edge. The outer edge 50 of each sector isprovided with spaced apart reinforcing members 52 that extend at rightangles to the plane of the sector from its outer edge and provide astrengthened edge area that can withstand hammering when the sectors areinstalled.

As a preliminary to installing the sectors 46, as shown in FIG. 3, thefirst series of nuts 42 are backed off an amount suflicient to allow theends of the sectors 46 to [fit between them and the flange 38 of thestern gland. One sector is preferably provided between each adjacentpair of nuts 42 so that sectors extend circumferentially around theentire flange while being adjacent to its face. These sectors can now bedriven inwardly to near the outer surface of the packing gland sleeveportion 34.

The packing gland 30 is now moved out of its normal position within thestern gland 26 by backing down the front nuts 44 on the studs 40adjacent its flange 32. This movement is terminated when the face 36 ofthe inner end of the packing gland moves slightly past the end face 54of the stern gland flange so that the old packing is visible, and isalso a distance sufficient to prevent the sectors 46 from engaging theend of the packing gland when they are driven inwardly. Now, as shown inFIG. 4, the rear nuts 42 are backed off a further amount until enoughspace is provided over each stud to accommodate a spacer 56. As shown inFIGS. 8-10, these spacers each comprise a pair of spaced apart invertedU-shaped end members 58 joined together by channel-shaped connector 60extending between the members 58 and having flanges that are spacedapart a distance slightly greater than the diameter of the studs 40.

With the spacers in position so that a stud is seated in thechannel-shaped connector of each, the nuts 42 are now taken up to bearagainst the spacers and cause them to hold the sectors against the sterngland flange.

The sectors 46 which are now held and guided at their ends by thespacers are driven radially inwardly between the end face 3 6 of thepacking gland and the old packing 28 and almost into contact with theshaft. This forms the circumferential barrier around the shaft thatholds the old packing in place and resists the outside water pressurealong the shaft. (See FIG. 10.)

In the next step, as shown in FIG. 5, the packing gland is now retractedeven further by backing off the front nuts 44 on the studs 40. When thisis done a space is provided at the end of the packing gland where newpacking material 62 can be placed in position around the shaft. As muchpacking as the space available will allow may be placed around theshaft. This packing material may be of any suitable type that iscommercially available so long as it is flexible and adaptable to bewrapped around the shaft.

With the new packing around the shaft the next step in my method is tocompress it circumferentially so that this material can be moved axiallyalong the shaft and into the end of the stern gland. To accomplish thisI utilize a band device 64 that fits temporarily at the end of thepacking gland around the packing material, completely covering it.Preferably, the band is made in two semi-circular pieces in order tofacilitate its installation. The ends of the adjoining band pieces areturned up to form flanges 66 through which bolts 68 are placed to drawthe band tightly around the packing material on the shaft. (See FIG.11.) Spaced apart circumferentially along one edge of both band piecesare a series of stop members 70 each having a radially extending face 72extending out from the band edge.

As shown in FIGS. 6 and 12 the front nuts 44 on the studs are now takenup to move the packing gland 30 axially along the shaft together withthe new packing material 62 which is retained by the band 64. As thepacking gland is moved, the new packing material moves under the spacersand the stop members 70 of the band eventually bear against the blockingsectors. (see FIG. 12.)

The barrier forming sectors 46 are now moved radially outwardly to allowpassage of the new packing material into the stern gland. Following thisthe front nuts 44 are taken up fully to cause the packing gland to moveforward and push the new packing material into place and to movepartially into the end of the stern gland. (See FIG. 13.)

The nuts 42 holding the spacers are now backed off slightly so that boththe spacers 56 and the sectors 46 can be removed. These nuts are nowfully taken up to bear against the flange of the stern gland.

From the foregoing it should be apparent that my method and theapparatus used in carrying it out provides a unique solution to theproblem of installing new packing to the propeller shaft of a ship. Iteliminates the need for any dry-docking or tipping of the shipheretofore required to overcome the problem of seawater pressure duringthe old repacking procedure and enables this repair to be performedefficiently and rapidly with a minimum of labor and expense.

To those skilled in the art to which this invention relates, manychanges in construction and widely differing embodiments andapplications of the invention will suggest themselves without departingfrom the spirit and scope of the invention. The disclosures and thedescription herein are purely illustrative and are not intended to be inany sense limiting.

I claim:

1. For use on a ship having a propeller shaft in a stern gland, apacking and a packing gland around said shaft, the latter being movablewithin said stern gland to retain the packing therein, a method foradding new packing around the shaft when the propeller shaft is belowthe water level but without water leaking into the ship, said methodcomprising the steps of:

installing a circumferential barrier extending radially outwardly fromthe shaft between the radial end face of the stern gland and the end ofthe packing gland with a portion of said barrier in engagement with thepacking in said stern gland;

holding said barrier with suflicient strength to overcome the forcetending to push the packing out of the stern gland;

retracting the packing gland far enough away from the stern gland toexpose an open space on the shaft adjacent the end of the packing gland;

placing a quantity of new packing material around the shaft adjacent theend of the packing gland; circumferentially compressing the new packingmaterial to minimize its outside diameter on the shaft; moving thepacking gland and the new packing up against the barrier; removing thebarrier; and moving the end of the packing gland partially into thestern gland with the new packing in contact with the old packing.

2. For use on a ship having a propeller shaft in a stern gland, apacking, and a packing gland around said shaft, the latter being movablewithin said stern gland to retain the packing therein, a method foradding new packing around the shaft when the propeller shaft is belowthe water level while preventing water from leaking into the ship, saidmethod comprising the steps of:

installing a plurality of circumferential barrier elements extendingradially outwardly from the shaft between the radial end face of thestern gland and the end of the packing gland with a portion of saidbarrier in engagement with the packing in said stern gland;

holding said barrier elements at their ends with sufficient strength toovercome the force tending to push the packing out of the stern gland;

retracting the packing gland far enough away from the stern gland toexpose an open space on the shaft adjacent the end of the packing gland;placing a quantity of new packing material around the shaft adjacent theend of the packing gland;

temporarily restraining the new packing material circumferentially tominimize its outside diameter on the shaft;

moving the packing gland until the new packing is located against thebarrier;

removing the barrier; and

moving the packing gland until its end extends partially within thestern gland and the new packing is contacting the old packing.

3. For use on a ship having a propeller shaft in a stern gland, apacking and packing gland around said shaft, the latter being movablewithin said stern gland to retain the packing therein, a method foradding new packing around the shaft when the propeller shaft is belowthe water level while preventing water from leaking into the ship, saidmethod comprising the steps of:

retracting the packing gland until its end is moved a short distancefrom the flange of the stern gland; driving a plurality of flat barriermembers inwardly toward the shaft between the radial end face of thestern gland and the end of the packing gland at circumferentially spacedapart intervals with a portion of each of said barrier members inengagement with the packing in said stern gland;

holding said barrier members with suflicient strength to overcome theforce tending to push the packing out of the stern gland;

further retracting the packing gland far enough away from the sterngland to expose an open space on the shaft adjacent the end of thepacking gland; placing a quantity of new packing material around theshaft adjacent the end of the packing gland;

temporarily restraining the new packing material circumferentially tominimize its outside diameter on the shaft;

moving the packing gland until the new packing is located against thebarrier members;

removing the barrier members; and

moving the packing gland until its end extends partially within thestern gland and the new packing is contacting the old packing.

4. For use on a ship provided with a propeller shaft in a stern glandhaving an end flange and studs mounted therein, a packing, and a packinggland around the shaft having one end movable within the stern gland anda flange at the other end with openings .alignable with said. studs,

an apparatus for installing new packing around the shaft and locating itwithin the stern gland adjacent the end of the packing gland in theretracted position, comprising:

a plurality of rigid sectors each having a curved inner knifelike edgelocated adjacent the surface of the shaft at the end of the stern glandand extending circumferentially around the shaft;

means for holding said sectors against the flange of the stern gland andthereby holding the old packing within the stern gland when the packinggland is retracted;

said sectors being removable when said packing gland is moved axially topress the new packing against the sectors after which said packing glandis movable to extend partially within said stern gland.

5. The apparatus as described in claim 4 wherein said means for holdingsaid sectors against the stern gland flange include a spacer on eachstud located between the stern gland flange and a nut on the stud forretaining and guiding the ends of said sectors when they are drivenradially into place.

6. The apparatus as described in claim 5 wherein each said spacercomprises a pair of spaced apart U-shaped plates interconnected by atunnel-shaped connector, one of said plates overlapping the ends ofcircumferentially adjacent sectors and the opposite plate forming abearing surface for a takeup nut on the stud.

7. The apparatus as described in claim 4 including a flexible bandaround said new packing material, means to tighten said band to decreaseits diameter, and a plurality of spaced apart projecting membersextending outwardly from one side of the band.

References Cited UNITED STATES PATENTS 362,355 5/1887 Bradford 277-l12,925,291 2/1960 Bygbjerg 277-4 SAMUEL ROTHBERG, Primary Examiner.

US. Cl. X.R.

